For the current memories, some employ the analog sense amplifier to perform the amplifying operation on signals on the bit-line pair. The analog sense amplifier has its advantages since its operation speed is fast. However, the analog sense amplifier is implemented by the differential amplifier, and thus it usually has the problem that the threshold voltages (Vth) of transistors are different because of the manufacturing problem (i.e., the mismatching problem), so that the analog sense amplifier has a disadvantage of voltage offsetting.
In addition, some memories employ the digital sense amplifier to perform the amplifying operation on signals. However, the digital sense amplifier must operate in full swing, thus it has a disadvantage of low operation speed.